A chromosome survey of five species of Cassidinae (Coleoptera: Chrysomelidae).

Chromosome numbers and sex-determining mechanisms of five species of Cassida beetles from different Spanish sources are given. C. deflorata Suffr. and C. flaveola Thunb. show a 8(11) + Xyp formula, C. vibex L. 9(11) + Xyp, and C. margaritacea Schall. and C. viridis L., 14(11) + Xyp. These chromosomal findings are in agreement with the current morphological systematics of Cassida. The karyotypes of C. deflorata, C. vibex and C. viridis are constituted by metacentric chromosomes mostly, but there are clear differences in the total complement lengths between the three species. The possible tendencies in the chromosomal evolution of Cassidinae beetles are also discussed assuming a primitive karyotype of 18 chromosomes.